code: def test_return_dataframe_merge_is_not_None_new_column_names_is_a_list(
      returns_frame_1,
  ):
      """
      Test that the dataframe returned when `merge_frame` is not None
      is a merger of the original dataframe, and the dataframe
      generated from the text processing. Also, the `new_column_names`
      is a list.
      """
  
      expected_output = pd.concat(
          [
              returns_frame_1,
              returns_frame_1["ticker"]
              .str.split(" ", expand=True)
              .set_axis(
                  ["header1", "header2", "header3"], axis="columns"
              ),
          ],
          axis="columns",
      )
      result = returns_frame_1.process_text(
          column_name="ticker",
          new_column_names=["header1", "header2", "header3"],
          merge_frame=True,
          string_function="split",
          expand=True,
          pat=" ",
      )
      assert_frame_equal(result, expected_output)
  
imports: import numpy
  import pandas
  import pytest
  from pandas.testing import assert_frame_equal
label_desc: Use image node_id 23 for calling a global function with example usage: test_return_dataframe_merge_is_not_None_new_column_names_is_a_list(returns_frame_1) without return types